Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

stargazine_ep14_banner.thumb.jpg.27eb9b06c9c8a1fe5ac3bae21c92743b.jpg

Alan64

Members
  • Content Count

    1,647
  • Joined

  • Last visited

Everything posted by Alan64

  1. There could be pieces of metal shards lodged inside, and from the factory. It wouldn't be the first time. When cleaning out the old grease, I've found that charcoal-lighter fluid, the kind for grilling outdoors, works wonderfully in removing all traces of the old grease, with rags and an old toothbrush. I did the same to my EQ-3. It's much smoother now. When re-greasing, only small amounts of the new grease are needed, particularly with the Super Lube.
  2. Super Lube is all I use, and for all of my astronomical needs. Believe it or not, it's even food-safe...
  3. Mark, congratulations on the new kit! You may find that the 150mm f/5 Newtonian will be quite ample, and for quite some time, especially with it mounted on a motorised mount. A 150mm f/5 is capable of powers ranging from a low and wide 19x, to 250x and beyond with the aid of 2x and 3x barlows, or without barlows at all but with very short focal-length eyepieces instead; 4mm and shorter, for example... http://www.365astronomy.com/Planetary-Eyepieces/#rfplist The focal-length of a 150mm f/5 telescope is 750mm. Eyepieces are numbered according to their focal-lengths. You simply divide the first by the second to find the power of any given eyepiece. The 4mm would realise a power of... 750mm ÷ 4mm = (188x) 750mm ÷ 3.2mm = (234x) 750mm ÷ 2.5mm = (300x), and the theoretical limit of a 150mm Newtonian. Those oculars sport large eye-lenses, and good eye-relief for eyeglass-wearers. They also have barlowing-elements, barlows essentially, built in. Separate barlows, however, offer a few advantages. An eyepiece combined with a barlow results in two powers per that one eyepiece. With a set of three eyepieces and a barlow, you would then have six different powers at your disposal. Another advantage is when you have an eyepiece like this 4mm(188x) orthoscopic laying about, like I do... Powerful, and most promising it is, but note the tiny eye-lens through which to observe. In addition, the eye-relief is very tight and in requiring placing the eye to where it almost touches the eye-lens of the eyepiece in order to see the full field-of-view. Instead of using that one, I usually prefer this wide-field 12mm with a 2.8x barlow, and for a simulated 4.3mm(174x)... I get practically the same magnification as the 4mm orthoscopic, but with the larger eye-lens and greater eye-relief of the more comfortable 12mm. Note how my combination there appears very much like the Lacerta(BST) eyepieces, with the built-in barlows, listed above. I have the previous models of these two barlows, and both are a great value for the price; extraordinary value actually... http://www.rothervalleyoptics.co.uk/antares-x2-twist-lock-barlow-lens-125.html http://www.rothervalleyoptics.co.uk/antares-x3-twist-lock-barlow-lens-125.html With a motorised mount, you certainly can make use of the shorter orthoscopics, however you'd be hard-pressed in using them with a telescope on a manual mount, as they have narrow fields-of-view(40° to 43°), compared to wide-field oculars. Orthoscopics, however, offer the sharpest views over that of any other eyepiece design, but less-expensive Plossls do give them a run for the money. Plossls, however, have even shorter eye-relief in the shorter focal-lengths(8mm and shorter) than that of orthoscopics, but with wider fields-of-view(50° to 52°). With a motorised mount, any object within the field of an orthoscopic(or any other ocular) will stand still, there in the center of the eyepiece even, and for as long as you'd like. Your telescope will come with a 2" focusser. For near to the lowest power practical, and the brightest field-of-view, this 2" 70° 38mm(20x) for example is quite popular... https://www.firstlightoptics.com/skywatcher-eyepieces/skywatcher-panaview-2-eyepieces.html ...and for scanning the star-fields of the Milky Way in summer, and observing the galaxy of Andromeda and the Pleiades in the fall and winter, among other nocturnal delights. Your kit will come with a 25mm(30x) Plossl, with a large eye-lens and quite good eye-relief, and very similar if not identical to the 25mm that came with my 150mm f/5... You'll be wanting more eyepieces in future, for different powers, of course. Cheers,
  4. If you're up to it, and good at tinkering, disassemble the mount-head, both axes one at a time, and clean out the old factory grease and re-lube with a quality grease. I use this for all of my astronomical equipment... https://www.amazon.co.uk/d/Lubricants/Super-Lube-Synthetic-Grease-Syncolon-Multi-Purpose/B000XBH9HI It's PTFE, or Teflon, based. There are other greases that can be used as well, and instructions online to help in disassembling.
  5. I lived in a large city when I was younger. At the time I had an 80mm f/11 refractor on an EQ-2. My family and I then relocated to a rural area, but only 20 to 25 miles south of that city, and over twenty years ago. I've had a 150mm f/5 Newtonian for almost four years now, but I didn't begin observing with it until two years later in 2015. I had not observed with a Newtonian before, and the experience was certainly eye-opening, and most rewarding. Over the last two years I devoted a good deal of time in observing only with that telescope... Its performance under a semi-rural night sky was such that I was inspired to flock and blacken its interior, for improved contrast; blacker sky backgrounds and object-details... Over time, I've also learned, and have almost mastered, the process of collimation... http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf All of these Newtonians -- the Sky-Watcher, the Celestron and Orion models -- are all manufactured by Synta Optical of China. The Sky-Watcher 150P-DS is Synta's finest, most well-equipped model. My Orion is the second most basic, with this Celestron model, the C6-N, being the most basic of them all... http://www.365astronomy.com/Celestron-C6-N-Newtonian-Telescope-Advanced-OTA-only.html My Orion has a better primary-mirror cell, but that's its only advantage over that one. Both the Orion and the Celestron have 1.25", single-speed, wonky plastic focussers; dreadful they are indeed. The models with the metal 2" two-speed focussers are not available in the U.S., as most imagers there use refractors for imaging. They are available in Canada however. The best one available in the U.S. is this Celestron model with a 2" one-speed focusser, and just like the Sky-Watcher 150P... http://www.highpointscientific.com/celestron-omni-xlt-150-newtonian-reflector-optical-tube-assembly-ota-31057ota?utm_source=google&utm_medium=cse&utm_term=CEL-31057-OTA&gclid=CKHXxMzA4NECFQwRgQodNisFuQ That Celestron has a 51mm secondary mirror. That of the 150P is probably the same, and configured for visual use only. My Orion has a 48mm secondary, as most probably does the basic Celestron model, the C6-N, and both most definitely for visual use only. That ends the treatise on the current state of the market regarding Synta's 150mm f/5 Newtonians. Now, a 150mm Newtonian may not knock your socks off there in the town or city, but under darker skies a 150mm really comes into its own, and will wow and amaze, for it's quite a bright, yet compact, telescope in its own right. Once in awhile, I like to hold a small point-and-shoot camera up to an eyepiece and snap a shot. Such is called "afocal" astrophotography. I'm limited to the brighter objects, like the Moon, but I also manage shots of the Orion nebula, and M13, a globular-cluster in the constellation Hercules. I only take these photos to illustrate what an eyepiece will show an observer during a live view... Not bad, eh? You can do the same yourself. In addition, I took those photos with the 150mm f/5 on the manual alt-azimuth as illustrated above. Other than the afocal technique, I do not image, as I prefer to see the objects in real time; albeit not as bright, colourful and detailed as those images taken over lengthy exposures to be sure. My images are only stills, and the result of the camera's shutter opening and closing in a single instance.
  6. Hello Mark, The Sky-Watcher "P-DS" series of Newtonians are configured for imaging, and come with 2" two-speed focussers. They are also good for visual as well, but not ideal in that they are fitted with larger secondary mirrors, for imaging, and therefore larger secondary obstructions which reduce contrast and sharpness; larger than those equipped with Newtonians configured for visual use only, like the Sky-Watcher "P" series of Newtonians. I can understand why you would be considering a 200mm Newtonian, and for visual, as the human eye is relatively weak and requires larger apertures, particularly under light-polluted skies. Cameras, on the other hand, do not require large apertures, as they're much more sensitive and more efficient at collecting light. Many image with the much smaller 130P-DS instead... https://stargazerslounge.com/topic/210593-imaging-with-the-130pds/ ...and it's not at all bad for visual use to boot. Also, the shorter the focal-length, the faster the camera takes a photograph. Maksutovs, which have the longest focal-lengths of all other designs, would be the slowest in taking a photograph of a celestial object. In addition, with a Maksutov, the mount chosen must be able to hold the telescope steady, rigidly, and for a long period of time. Maksutovs are used for imaging, but it's more of a specialty among advanced imagers, and oft requiring a very large mount in relation to the telescope; that is, for serious astrophotography, with a camera in place of an eyepiece. For afocal and EAA imaging, the requirements are not as critical. When imaging with a Newtonian, the collimation, the alignment of the mirrors within, becomes more critical and precise compared to what is required for visual observations. A 200mm f/5 Newtonian should require an EQ6-class mount, at least; for serious, prime-focus astrophotography. I would consider this kit... https://www.firstlightoptics.com/reflectors/skywatcher-explorer-150p-ds-eq-5-pro-goto.html ...and as a good balance between visual and imaging.
  7. My apologies, Jon, as I neglected to note that your kit came with a 3x barlow. You can certainly use that one, but with one caveat... Your barlow was at an effective 4.5x, with the barlow into the focusser first, then the diagonal, and then the eyepiece. A 4.5x is probably going to be a bit much for that telescope, depending on the eyepiece used. If you used the 25mm in that configuration... 400mm ÷ (25mm ÷ 4.5x = 5.5mm) = 72x; seems reasonable. If you used the 10mm, which is what I suspect that you used in fact, then... 400mm ÷ (10mm ÷ 4.5x = 2.2mm) = 181x, which is bit much for an 80mm refractor, per the 50x-per-inch standard; but not impossible. The only way that you can use the supplied 3x barlow is by placing the diagonal into the focusser first, then the barlow into the diagonal, and then the eyepiece into the barlow. A 2x barlow can serve as a 2x and possibly a 3x, hence the six magnifications that may be had from the 10mm and 25mm eyepieces, and as previously described. But the 3x cannot serve as a 4.5x, as you don't have enough focusser travel, inwardly I'm thinking, to reach focus at that multiplier(4.5x) with the 10mm. You may be able to with the 25mm, but apparently not with the 10mm, if in fact you used the 10mm at the time. In any event, let us know which eyepiece you used in that exercise.
  8. There's a go-to type kit that's quite popular, if you'd miss that of the iOptron, and within the price-range of the preceding... https://www.bhphotovideo.com/bnh/controller/home?O=&sku=681797&gclid=CMrFybTr19ECFQOewAoddaMCpQ&Q=&ap=y&m=Y&c3api=1876%2C92051678882%2C&is=REG&A=details The inside of a Maksutov, which uses a thick lens(meniscus) at the front, along with the secondary mirror, and the primary mirror at the rear... The focal-length of a 5" f/12 is quite long, as you can tell from that diagram, and 1500mm in length. Whereas your 10mm affords a power of 40x with the 80mm refractor, let's see what that same eyepiece would produce with the Maksutov... 1500mm ÷ 10mm = (150x) Quite a difference, eh? Maksutovs are primarily for moderate-to-high magnifications, and ideal for lunar and planetary observations, along with that of double-stars. They are also capable of observing many deep-sky objects, as most DSOs are in fact small. Of all the mirrored telescope designs, the Maksutov is the only design that has been described as being "refractor-like" in performance. You can even mount the 80mm f/5 achromat on the Celestron SLT mount, if you'd like, but the 5" Maksutov might be a bit too large for the iOptron mount, conversely. Incidentally, a refractor uses only two or three lenses, at the front, to form an image...
  9. To go larger in aperture, and for increased light gathering, you'll want a Newtonian, either a 6" f/5 on a tripod-type mount... ...or a longer 6" f/8 on a Dobson alt-azimuth. This kit can be motorised for hands-free automatic tracking of any object, but without the go-to of your iOptron, and the mount is the same as my own pictured on the right above, albeit with mine having been modified... https://www.optcorp.com/celestron-omni-xlt-150-newtonian-telescope-31057.html $478.94 with free shipping to Aurora via UPS Ground. The optical-tube would require rotation within its tube-rings whilst observing, and for a more comfortable focusser position, but not that difficult, not at all really, with a 6" f/5. There are even economical ways to make rotation even easier, via a simple mod. Or this... http://www.highpointscientific.com/celestron-omni-xlt-150-newtonian-reflector-optical-tube-assembly-ota-31057ota ...with this... http://www.telescope.com/Mounts-Tripods/Altazimuth-Mounts-Tripods/Orion-VersaGo-II-Altazimuth-Telescope-Mount/pc/-1/c/2/sc/35/p/10105.uts Together they would appear very similar to this... ...and easily moved about for short distances. Just point the tube straight up, then grab and go. A 6" f/5 is a bright, observationally-versatile and portable telescope, with magnifications ranging from a low and wide 19x, to 250x and beyond with the aid of 2x and 3x barlows. Here's a comparison between an 80mm(3.1") refractor and a 150mm(6") Newtonian, in so far as the light-gathering apertures... Note the small 7mm circle. That's our natural telescope, the pupil of the human eye, and dark-adapted. It gets us by from day to day, and even smaller then as it contracts from the sunlight, but at night it's not as good. Telescopes are relatively enormous extensions of our pupils, which is why we all love telescopes. Just how large of a "pupil" would you like? Note also the secondary obstruction of the Newtonian, and at 50mm(2") in diameter. Such reduces contrast and sharpness a bit, but it is what it is. Still, the primary mirror of that Newtonian would collect close to if not more than four times the light of the 80mm refractor. In addition, Newtonians are 100% false-colour free; no purple halos around brighter objects, in other words. Then there are the "Dobsonians"... A 6" f/8 Newtonian on a Dobson alt-azimuth... https://www.astronomics.com/6-f8-traditional-dobsonian-reflector_p20339.aspx A 6" f/8 would excel under light-polluted skies, where most of the visible objects are quite bright; the planets, the Moon, and the brighter stars. An 8" f/6 Newtonian on a Dobson alt-azimuth... https://www.telescopesplus.com/products/zhumell-z8-deluxe-dobsonian-reflector-telescope The Zhumell Z8 is the best kit sold in the States, and the same kit as the Revelation sold in the UK. Both are made by GSO(Guan Sheng Optical). They have machined two-speed focussers instead of the cast/molded one-speeds of the Orion and Sky-Watcher. The trunnion system of the Z8, where the tube joins the mount, and the RACI finderscope, are also superior to those of the Orion and Sky-Watcher. The Z8 costs a little more than the Sky-Watcher, and less than that of the Orion; odd, that, for the extras should set the Z8 at $100 more than the others. Well, let's not tempt fate. The inside of a Newtonian, which uses two mirrors, one large and one small, to produce an image...
  10. It was my pleasure, Jon. You may be surprised at how that diagonal will improve the views. Also, it will not introduce additional false colour, being that it's a mirror rather than a prism. If your refractor was the longer one as I had illustrated, I would've suggested the Celestron prism star-diagonal at that price-point. Synta's 80mm f/5 achromat, whether branded Orion, Sky-Watcher or iOptron, has a great following. Some users, if not many, replace the original 1.25" focusser with a 2", and for even wider views of the sky. Now, a 10mm and 25mm came with the kit. They should be Plossls(Synta), and practically identical to the ones I got with my Synta(Orion) 6" f/5 Newtonian... To find the power of your eyepieces, you simply divide the focal-length of the refractor by the focal-length of the eyepiece... 400mm ÷ 25mm = (16x), and binocular-like. 400mm ÷ 10mm = (40x), and for a closer look, but not by much. Depending on the quality of the main lens, or doublet, you should be able to realise 150x, per the 50x per inch standard on a night of average seeing, being that 80mm is 3.1". Therefore... 400mm ÷ 150x = a 2.7mm eyepiece Hmm, that's a tough one, but maybe not too tough. Let's say that you already have in hand the 2x barlow that I suggested; wishful thinking on my part, eh? Normally, you would place the new diagonal into the focusser first, then the barlow into the diagonal, and then the eyepiece into the barlow. Let's see what extra powers we get... 400mm ÷ (25mm ÷ 2x = 12.5mm) = (32x) 400mm ÷ (10mm ÷ 2x = 5mm) = (80x) So, by combining the 2x barlow with the two eyepieces that you already have, you then have a total of essentially four eyepieces, for 16x, 32x, 40x and 80x. Now, if you place the barlow into the focusser first, then the diagonal, and then the eyepiece, the 10mm and 25mm are approximately tripled(3x) in power... 400mm ÷ (25mm ÷ 3x = 8.3mm) = (48x) 400mm ÷ (10mm ÷ 3x = 3.3mm) = (121x) So, by combining the 2x barlow, before the diagonal and after the diagonal, with your two eyepieces, you get a total of six powers, and the equivalent of six eyepieces... ...16x, 32x, 40x, 48x, 80x and 120x, and all out of that one barlow. Later, you can add other eyepieces of different focal-lengths, and combine those with the barlow. Just one extra eyepiece thereafter will give you three new powers. It's interesting to note that a barlow may be configured as described only with telescopes that use diagonals: refractors, Schmidt and Maksutov Cassegrains, and even classical Cassegrains.
  11. Your 10" Dobsonian has a focal-length of roughly 1250mm. Have you found the range of magnifications, or powers, to your liking with said focal-length? For instance, a 32mm ocular affords a power of 39x, whilst with a 5mm(assuming you have a 2x barlow) at the other extreme: 250x. Has that range of powers, from a low 39x to a high 250x, been satisfactory? Eyepieces are static, unchanging, from a 4mm to a 40mm; but they provide a wide, dynamic range of powers when used with this telescope and that. Let's look at your prospects... A Celestron 11" Schmidt has a focal-length of 2800mm, and well over twice that of your present kit... 2800mm ÷ 32mm = (88x) That would be one of the lowest powers. A 6mm: (467x) The Meade 12" Schmidt has a focal-length of 3048mm. 3048mm ÷ 32mm = (95x) With that being one of the lowest powers. A 6mm: (508x) Most deep-sky objects are rather small, and those two telescopes would certainly bring them up close. Of course, low-power wide-field views are out of the question. If you are to choose one from the lot, for astrophotography, this one would be the one to get... "CGEM 1100 HD COMPUTERIZED TELESCOPE (by celestron) " The other three would be primarily for visual use, with eyepieces, per their type of mounts, and all for high-magnification observations.
  12. A fellow amateur, who lives in Denmark, saw a few of the Bresser refractors first-hand, and was of the opinion that they, the refractors, were a notch up in overall build-quality compared to those of Synta(Sky-Watcher, etc); for what it's worth. The primary mirror will be a parabola, of course.
  13. If you have recourse to recovering your funds, if it doesn't prove to be as advertised, I'd say go for it, and before someone else goes for it.
  14. Aside from the wrap, it nonetheless looks to be new, and is indeed a 150mm f/5 Newtonian; perfect. The image within the link is of the longer f/8 variant, which are usually mounted on a Dobson alt-azimuth or on a large equatorial(EQ-6).
  15. Hello Andy, "The telescopes will be used with an alt az mount Vixen Porta II or the Skywatcher AZ4 (not decided yet)." The AZ4 mount will support the Sky-Watcher 150P-DS, 150mm f/5, if you'd like the extra aperture... That telescope, incidentally, is Bresser's 150mm f/5. I have a 150mm f/5 Newtonian, and most often mounted on a alt-azimuth mount of a similar build as that of the AZ4... It's a good-sized telescope, but probably not as large as you might think at first, and with a standard table salt-shaker alongside to illustrate... I've found a 150mm f/5 Newtonian to be a great all-around telescope, with magnifications ranging from 19x, to 250x and beyond with the aid of 2x and 3x barlows, and for observing virtually everything in the sky; the gamut. Once collimation of a Newtonian is learned and mastered, and fairly quickly, it becomes quite the proverbial piece of cake. Once collimated properly, the telescope would require only very minor adjustments on occasion. It's the initial learning and mastering of the process that puts many people off, but after a time you would look back and wonder as to why people don't consider a Newtonian more often. The 150P-DS comes equipped with a metal 2" two-speed focusser, just as the 130P-DS; for a more precise focus, and in realising any given object at its sharpest. As to the optical quality, I sometimes take afocal photographs of a few objects, and simply by holding a small camera of sorts up to the eyepiece and snapping a shot, on the fly... My 150mm f/5 arrived as this, and as the Orion StarBlast 6... ...and a blast it has been indeed.
  16. Any and all optical accessories, and the cleanliness and clarity thereof, that are placed in the optical path, are going to affect the quality of the image there at the eyepiece or camera. I would exchange the entire set, and hope for the best. There's really no excuse for that, being that it's new. I ordered a set of coloured filters one day, many years ago, and all of them arrived, save the #80A(bottom right)... Time passed, yet I did not follow up with the vendor on the back-ordered filter. About two years later, it finally arrived in the post. I had forgotten all about it.
  17. Hello Sarah, The red-dot finder is integral to the cowling... There, the user incorporated what looks to be a rifle-scope, and in the original finder's stead. I wouldn't think that to be an option however. If I had said kit, I would install a Vixen-style shoe for either a proper red-dot or a 6x30 finderscope... http://www.teleskop-express.de/shop/product_info.php/info/p299_Sucherschuh---base-that-mounts-your-finder-scope-bracket-to-the-telescope.html That would require marking and drilling two holes into the optical-tube for the shoe, and perpendicularly to the length of the optical-tube... But that would require removing everything from the optical-tube, front and back, and so as not to damage the mirrors. However, that may be quite difficult to do with the Celestron. Still, it was assembled at the factory overseas, therefore it can be disassembled. Then to choose from one of these as the new finder... http://www.teleskop-express.de/shop/product_info.php/info/p3907_Celestron-6x30-Finder-Scope-with-Bracket---black--straight-view.html http://www.teleskop-express.de/shop/product_info.php/language/en/info/p303_Baader-SkySurfer-III---LED-Red-Dot-Finder-and-Solar-Finder.html You do, of course, have the option of leaving the original finder in place, as it's short and squat. A new red-dot finder should rise above it; a 6x30 finderscope definitely will. You also have the option of returning or exchanging the kit, and then to get this one... http://www.teleskop-express.de/shop/product_info.php/info/p1036_Skywatcher-Explorer-130P---130-650-mm-parabolic-Newton-on-EQ2.html I would choose that option myself. Else, you'll simply have to make do with the existing finder. Another option would be a 32mm(20x), or better yet, a 40mm(16x) Plossl eyepiece, to find the objects of interest with that, then to switch to an eyepiece of higher power for a closer look. Incidentally, you can motorise the mount in the RA-axis, and for automatic hands-free tracking of any object... http://www.teleskop-express.de/shop/product_info.php/info/p1025_R-A--tracking-motor-for-AstroMaster-EQ--CG3--mounts.html The motor-drive would also work with the EQ-2 mount of the Sky-Watcher variant.
  18. I have the same Synta Plossls that came with my Synta Newtonian... I looked through them once. Whilst the mirrors of the telescope itself are very good indeed, the bundled eyepieces are okay, but I have other eyepieces. Plossls have very short eye-relief when you choose below 10mm(120x). I have a Vixen NPL 6mm(200x), and I almost have to touch my eye to its lens, and in order to see the full field... ...but the view through it is like... . https://www.firstlightoptics.com/vixen-eyepieces/vixen-npl-eyepieces.html
  19. Yes, that's the same 80mm f/5 achromat as the Orion ST-80. It's branded "Sky-Watcher" as well, and they are configured primarily for low-power wide-field deep-sky. If you have the diagonal pictured in that manual, then that's a 45° Amici, and suitable only for daytime/terrestrial observations. If you don't have one already, then for astronomy, observing at night, you will need a 90° star-diagonal... http://agenaastro.com/gso-1-25-90-refractor-mirror-star-diagonal.html You might also want to consider a 2x barlow... http://agenaastro.com/antares-1-25-2x-barlow-lens-twist-lock-adapter-t-thread-ub2stl.html It will double the power of any eyepiece when the barlow is inserted into the diagonal. If I'm not mistaken, if you insert it into the focusser, then insert the diagonal and eyepiece, the power will be increased. In that your 80mm f/5 has a focal-length of 400mm, the 2x barlow will transform that into an effective 800mm or greater. In other words, the barlow will help in getting you closer to the objects of interest. However, being that the refractor is a fast achromat, a considerable amount of false colour will be seen when viewing brighter objects, of which you may find objectionable. Still, you can observe the dimmer objects up close, like the Trapezium star cluster of Orion.
  20. Hello ghostdance, Indeed it does have slow-motion controls. My own is an Astro-Tech Voyager I; not the current Voyager II sold in the States, but the I. I acquired it about ten years ago, and was able to get the pier-extension and eyepiece-tray at the time. It's currently available as the GSO SkyView Deluxe, here in the States, and in Europe, and in black... http://www.teleskop-express.de/shop/product_info.php/info/p1753_TS-Optics-Alt-Azimuth-Mount-Deluxe-with-worm-gears---up-to-8-kg.html This is how it appears currently... http://agenaastro.com/gso-skyview-deluxe-altaz-mount.html The pier, which is good for mounting longer telescopes, like refractors, is only available from Andrews in Australia, and near the bottom of this listing... http://www.andrewscom.com.au/site-content-section-10-guansheng.htm That is, if they get any more in stock. They do sell the mount with the pier included, I see. The GSO mount is a Taiwanese clone of the Takahashi Teegul, and possibly the 150... http://www.dark-star.it/astronomia-articoli-e-test/test-strumentali/takahashi-tg-150/ I've had great success in mounting my 150mm f/5 Newtonian on it... I like how the optical-tube is almost centered over the mount-head, and by virtue of the curved mounting arm. Stu has a point about the slow-motion controls, as it's quite the dance to track. Still, the mount may operated in either manner. In so far as its stability with a telescope of that size, I did take these afocal shots, through the eyepiece, and on the fly... I do use the slow-motion controls, particularly when taking afocal photographs.
  21. Hello Jon, I have an 80mm telescope. Does yours look like this... If so, then you might have this... ...or this... The first of those two is for deep-sky viewing, primarily, and the second can actually do both: lunar/planetary and deep-sky. Since you said that everything is tiny, I'm guessing you have the first. Do you have a range of eyepieces, and a 2x or 3x barlow?
  22. Hello, I have a Zhumell Z100, which is essentially the same telescope as the Orion SkyScanner 100mm and the Sky-Watcher Heritage 100P... The three telescopes, all 100mm f/4 Newtonians, have a focal-length of only 400mm. They're primarily for low-power wide-field views, but that hasn't stopped me from ramping up the magnification, and where observing the Moon and the planets is most beneficial. You will need at least a 2x barlow to combine with the eyepieces that will come with the kit. This is how the Moon will appear, and as my camera had snapped the shot through the 10mm included with my kit... Not bad, as I do see some craters, but you'll want to get closer, and a 2x barlow will help with that. A 2x barlow will transform the telescope from a fast f/4 to a moderate f/8; the latter being better suited for lunar and planetary, as well as for double-stars, globular clusters, etc. At one point, I barlowed the 10mm with my 2.8x Klee, for a simulated 3.6mm(111x), and managed to get a closer shot of the Moon... Therefore it is possible to reach the higher powers necessary, and with a barlow, perhaps even a 3x which will transform the telescope into a slow f/12, and ideal for your observing interests. Enjoy the new kit, and clear skies to you always.
  23. http://www.rothervalleyoptics.co.uk/antares-x2-twist-lock-barlow-lens-125.html http://www.rothervalleyoptics.co.uk/antares-x3-twist-lock-barlow-lens-125.html I've had quite the good fortune with my own, having witnessed snap-to focussing with the 3x, and a near-perfect star-test with the 2x...
  24. I may have a solution for you. This lens assembly was very dirty when I received it. It even had tiny paint specks on it, in addition to what appeared to be hard-water stains... http://www.boots.com/en/Ponds-Cold-Cream-Cleanser-50ml_1120639/ There are other varieties of Ponds cream, but get only the original "cold cream cleanser". It's been used for years to restore old camera lenses, and as you can see within my image, it's no wonder. After polishing the lens with the cream, and with clean fingers(no grit), wash with dish-detergent and hot water, rinse, then rinse with distilled water and allow to dry.
  25. You're most welcome, Ger. When you say "goto", is that a go-to mount alone that you have, or a go-to kit with another telescope mounted on it? A proper collimation of your f/4.4 Newtonian will prove most helpful when barlowing the 6mm and then aiming the telescope at the object of choice. An f/4.4 is quite fast, and where collimation is most critical. I look upon my Newtonians, and I see the focussers on the outside, and the large primary mirrors at the bottom of the tube. But that doesn't assure me as to whether or not my telescopes are capable of providing their best when observing. A collimation-cap does, however. I simply pop it into the focusser, aim the telescope towards a blank bright wall or other, then place a camera's lens over the pinhole of the cap, zoom in a bit, and snap a shot... I then see exactly what's going on inside the Newtonian, and to see if it needs adjusting. No, not in that case. I then know that I can pop in an eyepiece, like a 4mm orthoscopic, and see what I was after, sharp and clear. Collimation instructions... http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf In so far as the planets, Jupiter and Saturn are the most popular, and who can resist not turning one's telescope towards Venus. You may have seen Jupiter and Venus as this through your telescope... The cure for that is a variable polariser... https://www.firstlightoptics.com/moon-neutral-density-filters/variable-polarizing-moon-filter.html Such will allow you to see the coloured bands of Jupiter, and the Moon-like phases of Venus, and by dimming down the glare and brilliance. Enjoy your new kit, and clear skies to you always.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.